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Could someone explain me how to calculate "exp"?

Basically I have to calculate intrinsic density for silicon at T = 200K $$n_i=(N_cN_v)^{1/2}exp(-\frac{E_G}{2E_T})[cm^{-3}]$$

$$\sqrt{N_c N_v}=1.3173\times10^{19}$$ $$E_G=1.14736$$ $$-\frac{E_G}{2E_T}=-33.35$$

I need to calculate \$exp(-33.35)\$

How can I calculate \$exp(x)\$?

W5VO
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Tensio
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  • Nothing to do with electronic design. Question should be closed. – Leon Heller Apr 19 '12 at 22:28
  • yea I know, but I'm SO user and hoped I might get some help here, as this has nothing to do with programming :/ – Tensio Apr 19 '12 at 22:30
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    Maybe try http://math.stackexchange.com/ – Kris Bahnsen Apr 19 '12 at 22:31
  • Um, calculator? Am I missing something? – AngryEE Apr 19 '12 at 22:34
  • yep, it's a function and if I calculate exp(x) using wolframalpha I get correct solution but what does that function stands for and how can I calculate it using calculator? – Tensio Apr 19 '12 at 22:41
  • @AngryEE I agree it's off topic. For anecdotal context, I never saw this notation until I was half-way through college. People just started using it and assumed you knew what it meant. – W5VO Apr 19 '12 at 22:44
  • If you really want to calculate exp(x) (not just find its value), this Wikipedia article includes a power series approximation. – JRobert Apr 20 '12 at 16:59

1 Answers1

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\$exp(x)\$ can also be written as \$e^x\$. Most scientific/graphing calculators will have this as a function. The number e is a constant irrational number approximately equal to 2.71828183.

Note that Google will solve this if you use "exp(x)" as well as "e^x".

W5VO
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